European Bison in Russia – Past, Present and Future
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European Bison Conservation Newsletter Vol 2 (2009) pp: 148–159 European bison in Russia – past, present and future Taras P. Sipko Institute of Problems Ecology and Evolution RAS, Moscow, Russia Abstract The area of the European bison during historical time Holocene is discussed with addition of new information published in last years. Northern border of an area corresponds 60 0 N. The area included average and southern Urals Mountains, the south of Western Siberia. On the east the European bison lived up to the Altay Mountains and Lake Baikal. The same area at a red deer having similar ecological needs. Increase of inbreeding level considerably and negatively influences adaptable and reproductive opportunities of a bison. This circumstance is especially shown in case of its reintroduction in mountain areas. The basic projects on cultivation of the European bison in Russia are discussed. Keywords : European bison, geographical range, inbreeding, reintroduction Bison Habitat The studies on historical changes of European bison habitat are important both theoretically and practically. Historical geographical range of a species is the most favorable area for reintroduction and creation new free populations. In Pleistocene, the European bison range covered the most part of Eurasia (Flerov 1979). From the beginning of Holocene natural conditions changed (especially in the western part of the region). Glacier shield and vast pre-glacier lakes shortened and disappeared. Forest boundary migrated to the North. Humans occupied the area. Snow cover became deeper and lasted longer and become a limiting factor of European bison distribution at the Russian plain. All factors mentioned above served in drawing of northeastern boundary of European bison range in historic time (Heptner et al. 1961). Observations on progress in adaptation of European bison in Vologda oblast (59 °–60 °N) and American bison at the Polar Urals (68 °–69 °N) show that distribution of European bison was limited more by anthropogenic influence then by snow cover. The northern boundary of European bison range at the Russian plain reached probably 60 °N, along the water divide of the Polar Ocean and the Caspian Sea (Fig. 1). At the historic time broadleaves forests reached 60 °N (Popadiuk et al. 1994). European bison inhabited the southern Finland (Kalela and Salmi 1944, cit. after Sokolov 1959). European bison fossils dated about 17 Century were found at the shore of the Ladozhskoye Lake and near Novgorod (Sokolov 1959). Taras P. Sipko 149 Figure 1. European bison range at the end of Holocene European bison inhabited Novgorodskaya area and surrounding districts (Bogdanov 1889; Sokolov 1959). In XVII-XVIII centuries European bison were mentioned in Kostromskaya region and in the Volga valley (Dolmatov 1849; Kulagin 1919), as well as in Vyatka area and Kazan’ region (Ruzski 1898). European bison fossils dated as 4000 years B.C. were found in the middle reaches of the Pechora river (Ponomariev 2001; Smirnow 2002). The same was the habitats of the red deer (Heptner et al. 1961), while currently the same area represents habitats of wild boar (Danilkin 2002) and roe deer (Danilkin 1999). In historical times European bison distributed to the south Urals. At the 1st Millennium B.C. European bison inhabited steppe-forests of trans Urals and west Siberia (Smirnov 1976; Kosincev 1982, 1986, 1988), in Holocene the animal still inhabited the Kuznetsk depression (Wiereshchagin 1956; Alekseeva 1980), and in VIII-X centuries made a part of mammal fauna in the Altay and Baikal regions (Ermolova 1978; Okladnikov, Kirilov 1980; Smirnov 1980; Danilkin 2005). Thus reconstructed borders of European bison and red deer habitats closely overlapped (Fig. 2). It is note-worth that ecological demands of both European bison and red deer are very close (Baskin 1979). 150 European bison in Russia – past, present and future Figure 2. Red deer range at the end of Holocene Inbreeding level Slatis (1960) underlined high inbreeding rates of European bison. Inbreeding coefficients were determined at the end of 80s of XX century on the level 26.28% for the Lowland-Caucasian line and 43.98% for Lowland line (Olech 1998). According to Kislovskyi (1965) it means too close inbreeding or incest. Besides all 12 predecessors themselves got high level of inbreeding (Sipko 2002), though the fact was not taken into consideration in calculations. The only exclusion was the outbreed bull named Kaukasus, which was caught in free living population in Caucasus. As calculation show, if effective population size is Ne = 50, inbreeding coefficient increases 1% per generation (Soule 1980). In European bison breeding centers in Russia effective size of populations never exceeded 10 so level of inbreeding increased more than 5% in each generation. We believe that a European bison generation is about 5 years in wild and about 8 years in captivity. It means that animals of each new generation got higher coefficient of inbreeding and consequently lower genetic polymorphism. As a result, adaptation potential and reproductive abilities of animals decrease. Data on reproduction of European bison relocated to the Caucasus (Table 1) prove the conclusion. It is easy to note that the later were bison reintroduced the worse was progress of the population started from the similar number of released animals. In spite of significant number of founders, reproductive success is Taras P. Sipko 151 Table 1. Reproductive success in populations of the European bison population Number of released animals Years of Population size after creations total females 30 years Caucasus The Kavkazsky Reserve 20 4 1940–1959 1300 Nal’chik hunting a facilities, 35 17 1959–1967 380 Kabardino-Balkariya Tseysky zakaznik and Severo- 48 32 1964–1968 270 Osetinsy Reserve Teberdinsky Reserve, Arkhyzsky 29 13 1968–1981 55 cluster Assincky zakaznik (the Cheche- 49 26 1970–1975 44 no-Ingushsky Reserve) Canada Mackenzie (American bison) 18 (16) 10 1963 1700 Carpathians Bieszczady 63 29 1963–1982 241 Bukovynska 23 14 1970–1977 225 obviously lower comparing with non-breed population from the Caucasus Natural Reserve or population of American bison from Mackenzie, Canada. The conclusion is that animals from nurseries are not suitable now for successful reintroduction to the Caucasian Mountains as well as, probably, to re-acclimatization in the Carpathian Mountains. Regulation of inbreeding level in Russian bison centers started in 90 ties due to mass import of animals from west European zoos with assistance of WWF. Positive influence of such “blood refreshing” cannot last longer then 2–3 generations as effective number of population remains low and bison-incomers are descendants of the same ancestors. Main projects on European bison breeding Scientific achievements and practice of conservation of rare animal species in the XX Century led to a “rule of 50\500” (Soule 1987). According to the rule, the effective number of 50 animals is sufficient for a short period of survival of population and saving of its genetic polymorphism, while long period of species flourishing needs an effective number of 500 animals. Only then necessary adaptations appear to keep the species safe with its evolutionary potential under constant changes of surrounding environment. Effective 152 European bison in Russia – past, present and future number (Ne) depends on the number of animals with high reproductive ability, on sex rate in a population as well as on inbreeding (Kaidanov 1996), in the fact very important for European bison. Generally Ne is about 25–35% of the total number of ungulate population. Thus, only a sustainable population of 1.500–2000 of bison could guarantee bison conservation. Besides, such circumstances like political situation, natural resources, epizootic disasters and many others have to be taken into account. The larger distance between two lands the lower probability that a disaster at one land will repeat at the other. Thus stability of species demands at least two large populations, significantly separated. There are no suitable ranges in west Europe and only Russia could provide perfectly fitting habitats. Total number of European bison in the world is less than 4000, besides high mortality and low level of reproduction (3–6% per year) prevent creation of necessary large population in visible future. We need concentration of all breeding resources of the world to solve the problem. Altay region European bison were introduced to the Altay region in 1982–1984 from the Prioksko-Terrasny breeding center. At the beginning there were 12 animals (3 bulls and 9 cows) and one cow perished just a month later. All animals belonged to Lowland line, founded by 7 (later 5) founders only (Sipko 2002). All these animals were relatives. The bull Moran (N ° 2729 EBPB) was already a father of two and, till 1987 was the main male. The goal of relocation was restoring recently extirpated European bison to their former range. European bison is an autochthonous species for Siberia and especially for Altay. We believe that the last animals lived in mountain valleys till XVIII (Wieresh- chagin 1956). Steppe-forest zones in mountains and valleys are perfectly suitable ranges for free roaming bison. The breeding center occupies north west Altay mountains, with elevations 600–1400 m. above sea level. The average year temperature is +2–3 °C; in July +17 °C; in January –14 °C. Vegetation period lasts 170 days. Annual precipita- tion is 500–700 mm, the highest in summer (Pieskova, Popov 1987), so snow cover is moderate. There were 41 European bison in the breeding centers in 2008 (15:26). Animals are strong and proportionally built with well developed, unaffected limbs. The latter means a good adaptation to life in mountains and dissected landscapes. Observation on bison during 25 years proved the success of adaptation process (Pieskova, Popov 1987; Popov 2000; Sharshov 2003), in spite of low adaptation abilities of bison from Lowland line. (As it was mentioned above, this line is highly inbred).